Valve sealing method



March 1967 E. F. PERLOWSKI, JR- 3,308,599

VALVE SEALING METHOD 2 Sheets-Sheet 1 Filed June 12, 1964 INVENTOREDWARD F. PERLOWSKLJR.

my I? flak HIS ATTORNEY.

March 1967 E. F. PERLOWSKI, JR 3,3 8, 9

VALVE SEALING METHOD Filed June 12, 1964 2 Sheets-Sheet 2 IJN INVENTORWARD F. PERLOWSKI,JR. Quiz/77* HIS ATTORNEY.

United States. Patent Ofiice 3,308,599 Patented Mar. 14, 19367 YorkFiled June 12, 1964, Ser. No. 374,692 4 Claims. (Cl. 53-22) Thisinvention relates to a valve sealing method and apparatus and, moreparticularly, to a thermoplastic valve seal and a method of operationthereof.

Prior art valves and the methods of operation thereof have provenunsatisfactory in applications requiring the handling of fluids inevacuated systems. A particular example of such fluid handling systemsand the difficulties introduced thereby is found in the manufacture oflight valve tubes for providing visual reproduction of televisionsignals by a light projection system. In such light valve tubes, oil isstored within a reservoir within the tube and deposited as a thin filmon a transparent, flat support member having a transparent conductivecoating on the opposite, parallel surface thereof. The scanning electronbeam performs a raster scan on the oil film, electrostatic chargeattraction between the electrons thus deposited on the oil film and theconducting coating causing the oil film to be deformed. The light valvetube forms a portion of a Schlieren optical system wherein, by theprojection of light through the optical system, the oil film, due to itsdeformation, diffracts the light rays passing therethrough forsubsequent projection to a viewing screen for reproducing a televisionimage.

Since light valve tubes employ a scanning electron beam, they must bedegassed in the manner of standard cathode ray tubes, the degassingcomprising a high temperature baking and evacuating of the tube. The oilfilm cannot be introduced into the light valve tube until completion ofthe degassing, since the high temperature would cause it to evaporate.Therefore, the oil must be kept in a second container, suitably a smallcapsule, introducing the further requirement that the oil capsule alsomust be degassed by an evacuating system, independently of the lightvalve tube;

It is desirable that the aperture or passage in the oil capsule throughwhich it is evacuated during the degassing also provide the passagethrough which the oil flows from the capsule for introduction into thelight valve tube. Therefore, valve means must be provided for sealingthe oil capsule, following its evacuation, at the evacuating aperture.Further, the valve must permit interconnection of the oil capsule andthe light valve tube while maintaining isolation therebetween duringdegassing of the latter. Finally, the valve must be operable, follwingthe degassing of the light valve tube, to permit the oil to flow fromthe capsule into the reservoir of the light valve tube, preferably in aminimum amount of time, while avoiding, at all times, any contaminationof the fluid.

Valve apparatus taught in the prior art, such as stopcock valves,generally are operated by a mechanical sliding or rotation of an elementfor engaging two surfaces at a sealing interface. Such surfaces must beaccurately ground to assure a tight, hermetic seal, resulting in arelatively high cost of such valves. The frictional engagement of thesurfaces at the sealing interface, a requisite of the tight hermeticseal, contributes to wear and deterioration of such valves and aresultant limited life-span. The high maintenance cost of such prior artvalves is further compounded by their difficulty of replacement,requiring a mechanical severing from the chamber with which they areemployed and the joining to the chamber of a new valve inhermetically-sealed fashion. Many prior art valves also require metal toglass interfaces, such interfaces not only being difficult and expensiveto form to assure the absence of leakage therethrough, but also beingsubject to fracture or rupture due to the unequal thermal coeflicientsof expansion of the two materials.

To operate a prior art valve, there is generally required a mechanicalconnection passing through the exterior walls of the valve to provide anoperating arm or lever. This passage through the wall of the valveinherently introduces a leakage path, limiting the ability of the valveto withstand ambient pressures for maintaining a vacuum within achamber.

Prior art valves of the internally-operated variety, such as rupturediaphragms and fractura'ble glass seals, are unsatisfactory in that theycan be operated only to open, and not close or seal a passage oraperture. Since they have only this unidirectional mode of operation,they are unsatisfactory for the application contemplated by thisinvention and illustrated hereinbefore, inasmuch as the oil capsulewould be required to have a second outlet for connection to anevacuating system. Further, the second outlet must still be providedwith a valve if the capsule is to be capable of being removed from theevacuating system for use at a later date. To facilitate mass productionof light valve tubes, it is essential that the oil capsules, followingdegassing, be hermetically sealed to permit their removal from theevacuating system so that they may be produce-d in advance and storedfor subsequent use in a production line. In addition, the method ofopening such rupture diaphragms and glass seals, namely the breaking orrupture thereof, as their name implies, introduces the foreign matter ofthe valve material into the fluid passing from the capsule into thereservoir in the light valve tube. Rupture diaphragms and glass sealsare also undesirable in that they are inherently capable of only oneoperation and therefore are very expensive to employ.

In addition to the above-noted deficiencies, the valves provided by theprior art generally are neither capable of maintaining the isolationbetween the capsule containing the fluid and the light valve tube duringthe bake-out and degassing of the latter, nor do they permit the rapidtransfer of the writing fluid into the light valve tube following thebake-out and evacuation thereof. Thus, the apparatus and methods of theprior art for effecting transfer of a fluid between two independentlyevacuated containers not only have been very expensive in costs ofcomponents and operation, but also have not been successful inmaintaining the degree of evacuation and the contamination-freeconditions which are essential for proper functioning of the completedlight valve tube.

It is therefore an object of this invention to provide an improved valvesealing method and apparatus for effecting an hermetically-tight sealwithin an enclosed chamber.

Another object of this invention is to provide a valve sealing methodand apparatus for employment within an enclosed chamber and operablefrom a position totally externally of the enclosed chamber for closingand opening and unsealing a defined aperture therewithin.

A further object of this invention is to provide a valve sealing methodand apparatus for facilitating interconnection of first and secondenclosed and independently evacuated chambers in anhermetically-isolated manner.

It is still another object of this invention to provide a valve sealingmethod and apparatus for effecting an hermetically-tight seal at apredetermined position within an enclosed chamber following evacuationthereof.

It is still a further object of this invention to provide a valvesealing method and apparatus for effecting an hermetically-tight seal ata predetermined position within an enclosed chamber following evacuationthereof and for providing opening of the valve seal from a positiontotally externally of the enclosed chamber to provide communication witha second, independently evacuated chamber.

Still another object of this invention is to provide a valve sealingmethod and apparatus for facilitating interconnection of first andsecond enclosed chambers and operable for permitting communicationtherebetween with subsequent hermetic sealing of the second enclosedchamber.

Other objects and advantages of the present invention will be apparentto those skilled in the art from the following detailed description ofthe invention.

In accordance with a preferred embodiment of the invention there isprovided a capsule having neck and tank portions, the neck portion beingadapted for interconnection with a light valve tube. A hollow, dependingside arm is formed on the neck portion, communicating with the interiorthereof, a valve member and a small quantity of sealing fluid beingreceived within the side arm. An aperture-defining constriction isprovided in the neck portion intermediate the side arm and the tankportion and designed for receiving the valve member to seal the tankportion of the chamber. The side arm is heated to render the sealingfluid fluent, permitting the valve member to be released from the sidearm upon appropriate tilting of the capsule. As the capsule is returnedto an erect position, the valve member falls by force of gravity and isreceived within the constriction, the sealing fluid flowing about thevalve member and the constriction to seal the aperture. Following theevacuation of the capsule and the sealing of the tank portion, thecapsule is joined at its neck portion in hermetically sealed fashion toa feed tube extending through the envelope wall of a light valve tube.The feed tube extends within the light valve tube to providecommunication with a reservoir therein. The valve sealing apparatus ofthe invention isolates the tank portion of the capsule from the lightvalve tube while the latter is degassed. Following the degassing, thelight valve tube is cooled to ambient temperature and the valve sealingapparatus of the invention opened by externally heating theaperture-defining constriction. Following the bake-out and dcgassing ofthe light valve tube the latter is hermetically sealed and removed fromthe evacuating means and cooled to ambient temperature. The fluidcontained within the tank portion of the capsule is transferred to thereservoir by opening the valve provided by the valve sealing apparatusof the invention which previously had maintained the isolation. Thisopening is eifected by heating the constriction to render the sealingfluid fluent, whereby the valve member is released from the aperture andfalls onto a suitable retaining screen. The writing fluid then readilyflows from the capsule, through the neck portion thereof, and throughthe feed tube into the reservoir. The feed tube is pinched closed,providing an hermetic seal. The capsule subsequently is removed from thelight valve tube, thus completing the operation.

For a better understanding of the invention, reference may be made tothe following drawings in which:

FIGURE 1 shows the capsule and the valve sealing apparatus positioned ina preliminary step of the sealing method,

FIGURE 2 shows the capsule and the valve sealing apparatus in anintermediate step of the method,

FIGURE 3 shows the valve sealing apparatus in sealing position,

FIGURE 4 shows the capsule interconnected with a light valve tube at anintermediate step in the transfer of writing fluid therebetween,

FIGURE 5 shows a small portion of the apparatus of the invention incross-section to illustrate a retaining screen for holding the valvemember in the step of the method shown in FIGURE 4,

FIGURE 6 shows the final step in the method, and

FIGURE 7 shows alternative embodiments of the apparatus.

As shown in FIGURE 1, the valve sealing apparatus of the invention isadapted for employment in a capsule 1 including a neck portion 2 and atank portion 3. A side arm 4 is formed on the neck portion 2, the hollowinterior portion thereof communicating with the interior of neck portion2. The side arm 4 is oriented in depending relation to the neck portion2 for the vertical orientation of the capsule 1 shown, the angle beingapproximately 5 to 10 below a horizontal plane.

Positioned within the side arm is a valve member or plug 5 and a smallquantity of sealing fluid 6. Valve member 5 may take variousconfigurations, but is shown as being pear-shaped, including a narrowend 5a and a bulbous end 5b. Sealing fluid 6 is highly viscous,approximately the consistency of a solid, at room temperature, butbecoming fluent upon suflicient heating.

An aperture 7, defined by a constriction 8, is provided intermediate theside arm 4 and the tank portion 3, the constriction 8 interconnectingthe neck portion 2 and the tank portion 3 in FIGURE 1. The constriction8 establishes a valve sealing position within the capsule 1 by which thetank portion 3 thereof may be hermetically sealed. A quantity of fluid 9is received within the tank portion 3. The nature of the fluid 9 isdetermined by the system to which it is to be transferred, as explainedmore fully hereinafter. A stirring magnet 10 may be provided within thetank portion 3 and may be mounted therein by stud 11 aflixed to thebottom of tank portion 3. A driver magnet 12 is positioned externally ofthe tank 3 and adjacent stirring magnet 10 for rotation by suitablemeans (not shown) to drive stirring magnet 10 into rotation for stirringthe fluid 9.

An interconnecting means 13 is provided for joining the capsule 1 toother apparatus. Interconnecting means 13 includes a flexible tube 14and ends 15 and 16, each end 15 and 16 including an interior, or femaletaper portion. Neck portion 2 is provided with a tapered end section 17to form a standard hermetically-tight taper joint with the end 15 ofinterconnecting means 13. The female taper at end 16 provides anhermetically-tight joint-with interconnecting means of associatedapparatus (not shown).

In operation, following the reception of the fluid 9 within tank portion3 as shown in FIGURE 1, interconnecting means 13 is attached to thecapsule 1 and to suitable evacuating means (not shown) for evacuatingthe capsule 1. Stirring magnet 10 assists in the evacuation by exposingair trapped within the fluid 9 at its surface.

Following the evacuation of chamber 1, heat is applied to the side arm 4to render the viscous sealing fluid 6 fluent. As shown in FIGURE 2, thecapsule 1 then is tilted such that side arm 4 is angularly inclinedslightly above a horizontal plane, permitting valve member 5 to dropinto neck portion 2. The angle of tilt is not critical, it beingsufiicient to raise side arm 4 approximately 5 to 10 degrees above ahorizontal plane. Inasmuch as the sealing fluid 6 remains relativelyviscous, even after heating, and since valve member 5 is partiallyimmersed therein, a slight tapping on the side of neck portion 2opposite to that of the side arm 4 may be necessary to assist inextricating valve :member 5 from the fluid 6 and removing it from sidearm 4. Upon coming in contact with the cooler regions of neck portion 2,the sealing fluid 6 is cooled and becomes more viscous, adheringthereto. A thin film of the sealing fluid 6, formed on the valve member5 while the latter was within the side arm 4, remains in a fluent statethereon due to the heat retained by the valve member 5.

Valve member 5, by force of gravity, falls into the aperture 7, thenarrow end portion 5a thereof extending into the aperture and thebulbous end portion 512 engaging the interior walls of the constriction8. The thin film of sealing fluid 6 retained in a fluent state on thevalve member 5 flows about the interface thereof with the constn'ction 8to form a preliminary seal. Since the majority of the sealing fluid 6remains solidified on the neck portion 2, as shown in FIGURE 2, relativefreedom is provided for manipulating capsule 1 to assure a properorientation of the valve member 5 within aperture 7 in effecting thepreliminary seal.

Following the positioning of valve member 5 within aperture 7 additionalheat is applied to the neck portion 2 in the region thereof to which thesealing fluid 6 is adhering to render the latter fluent. The sealingfluid 6 then flow-s into the constricted region 8 as shown in FIGURE 3.After cooling to ambient temperature, the sealing fluid 6, incombination with the valve member 5, provides an hermetically-tight sealof the aperture 7. Interconnecting means 13 is now removed from theevacuating means (not shown), the valve sealing apparatus of theinvention maintaining the evacuated condition of tank portion 3 ofcapsule 1 against ambient pressures.

The specific application of the valve sealing apparatus and method ofthe invention described herein is supplying a writing fluid to a lightvalve tube 18, as shown in FIG- URE 4. Since the light valve tube formsno part of this invention, the only portions thereof which are showninclude a flared envelope 19, a cylindrical neck portion 20, and areservoir 21 within the envelope 19.

A feed tube 22 extends through the envelope 19, in hermetically sealedrelationship therewith, to a position vertically above the reservoir 21.The feed tube 22 may be formed of copper or other suitable malleablematerial. Feed tube 22 is provided with end member 23 having a maletaper end portion for forming an hermetically-tight taper joint with theend 16 of interconnecting means 13.

The light valve tube 18 includes a cathode gun section, generallyincluded within the neck portion it is therefore essential that thelight valve tube 18 be subjected to a standard bake-out and degassingprocedure to enable operation of the electron gun. The valve sealingapparatus and method of the invention maintain the writing fluid 9 inisolated condition within the tank portion 3 of capsule 1 during thebake-out and degassing of the light valve tube 18.

After the light valve tube 18 has cooled to ambient temperature, thevalve apparatus of the invention is opened to permit the writing fluid 9to flow into the reservoir 21. The valve member 5 and the sealing fluid6 are removed from their sealing position within aperture 7 by applyingheat to the exterior of constriction 8. The sealing fluid 6 is renderedfluent and begins to flow, thereby releasing valve member 5. Sealingfluid 6 continues to flow, by force of gravity, along the interior wallsof neck portion 2 until it reaches the cooler portion thereof, whereuponit substantially solidifies and adheres thereto. The full dimension ofaperture 7 is opened, thereby permitting the writing fluid 9 to flowreadily therethrough.

As shown in FIGURE 5, a retaining screen 24 is provided within the end15 of interconnecting means 13. Following its removal from the aperture7, valve member 5 falls into the end 15 by force of gravity and isretained therein, as shown, by the retaining screen 24. Thecrosssectional view of FIGURE 5 also illustrates the hermetically-tighttaper joint formed by the male taper end portion 17 of the neck 2 andthe interior female taper of the end 15.

Following the transfer of the writing fluid 9 to the reservoir 21, thefeed tube 22 is pinched together, forming an hermetic seal. Feed tube 22then is severed above the pinched position, and the capsule 1 and itsassociated apparatus is removed from the light valve tube 18. The stubof feed tube 22 which remains is preferably an inch to three inches inlength, the collapsed end portion thereof being coated with an epoxyresin to assure the adequacy of the hermetic seal.

The valve member 5 may be retrieved from its retained position withinthe end 15 on retaining screen 24 and employed with the capsule 1 in asubsequent operation. In addition, the sealing fluid 6 may be heated andcaused to flow back into the side arm 4, whereby it, too is reusable.

Alternative embod-iments of an aperture-defining constriction and avalve member are illustrated in FIGURE 7. Neck portion 2' has walls ofconstant diameter and includes therein aperture-defining members 25 forproviding an aperture 7'. The members 25 may be hermetically sealedwithin the interior of neck portion 2 or, as a further alternative, maybe formed integrally therewith.

FIGURE 7 also shows a valve member 26 having the same externalconfiguration as the valve member 5 but including therein a permanentmagnet 27. An external magnet 28 may be used to facilitate movement ofthe valve member 25 to its plugging position within the aperture 7.

It is apparent that, if desired, separate side arms may be employed forindependently retaining, or withholding the valve member such as 5 or 25and the sealing fluid 6, the purpose of the withholding being to assurethat the aperture 7 or 7', respectively, remains open.

In certain applications, such as the one illustrated, of supplyingwriting fluid to a light valve tube, it is essential that the transferof the writing fluid be performed under contamination-free conditions.Therefore, the capsule 1, the interconnecting means 13, and the feedtube 22 preferably are selected to be of materials which are not solublein the writing fluid 9. A suitable material for the capsule 1 and thevalve member 5 is glass, and for the flexible tubing 14 and the feedtube 22 is copper. The use of copper for the tube 22 is also desirablein that it is sufficiently malleable so as to permit the metal in thewalls thereof to collapse and flow together, when pinched, for providingthe hermetic seal shown in FIGURE 6. Writing fluids which workeffectively in light valve tube-s comprise polybenzyl toluene,polybenzene benzene and polybenzyl biphenyl. Since the amount of writingfluid relative to the amount of sealing fluid 6 will be in the range of250 gms. to of a gm., the possible percentage poisoning of the writingfluid during the transfer thereof from capsule 1 into reservoir 21 isrelatively minute. However, to obviate any such poisoning which mightoccur, the sealing fluid 6 may be of the same chemical composition, butof a much higher viscosity than the writing fluid 9. In'the alternative,the sealing fluid 6 may be selected from fluids which are insoluble inthe writing fluid 9. In any event, the material constituting the.sealing fluid 6 should either be substantially insoluble in the writingfluid 9 or, if soluble therein, of a non-poisoning or non-contaminatingnature.

The valve sealing apparatus of the invention provides a substantialnumber of distinct advantages over the techniques and apparatus of theprior art. The utilization of the translatable valve member 5 assures aneffective, strong, and highly reliable hermetic seal of the relativelywide-dimensional aperture. In one application employing the valve of theinvention, 40 cc. of fluid was transferred in 1.5 minutes whereasperiods of up to one hour were required for transferring the samequantity of fluid when employing prior art valves. Further, valve member5 need not be accurately ground to form an hermetic seal with theinterior walls defining the aperture 7 since sealing fluid 6 performs adual function, not only mechanically retaining valve member 5 in thesealing position, but also hermetically sealing the interface. Vacuumsattained in a system employing the valve sealing apparatus of theinvention have ranged from 10" to l0 torr. The seal, once effected, isextremely stable and, in a series of applications, the change in thevacuum levels ranged from 0.7 10 torr to only l4 10 torr, for periods inexcess of a month, clearly demonstrating the reliability andeffectiveness of the valve sealing apparatus of the invention. Uponremoval of the valve 7 member 5 from the sealing position within theaperture 7, however a relatively large orifice is provided through whichthe fluid may flow for rapid transfer thereof to a receiver within asecond enclosed capsule or chamber.

In addition to being relatively low in initial cost of components andconstruction, the valve sealing apparatus oi the invention is reusablefor substantially an unlimited number of times. With the exception ofaccidental breakage, there are no parts subject to any substantial weardue to mechanical interaction or frictional engagement. Further, suchwear which will occur is inconsequential since the sealing fluid 6performs the hermetic sealing function at the interface of valve member5 and the walls or construction defining the aperture 7. In addition,the simplicity of the apparatus enables its cleaning in a very easymanner, and also affords a minimal cost of maintenance and repair eitherin use, or in preparation of reuse.

Although shown in only one specific, preferred embodiment, the valvesealing apparatus of the invention is subject to numerous modifications,and the method and varieties of employment thereof will readily beobvious to those skilled in the art. Thus, it is intended by theappended claims to cover all such embodiments and applications thereofwhich fall within the true spirit and scope of the appended claims.

What I claim as new and desire to be secured by Letters Patent of theUnited States is:

1. A valve sealing method for selectively hermetically sealing oropening an aperture defined by a constriction located intermediate neckand tank portions of a capsule comprising the steps of:

(a) providing a hollow side arm on said neck portion in communicationwith the interior thereof,

(b) positioning a valve member and viscous sealing fluid in said sidearm, said sealing fluid maintaining said valve member therein,

() heating said side arm for rendering said sealing fluid fluent forenabling release of said valve memher from said side arm,

(d) tilting said capsule for releasing said valve memher from said sidearm,

(e) transferring said valve member to said constriction,

(f) heating said sealing fluid and causing it to flow into sealingrelation with said valve member and said constriction, and

(g) cooling said sealing fluid for completing the hermetic valve seal.

2. A valve sealing method as recited in claim 1 wherein there areprovided the following steps for opening the hermetic valve seal:

(a) inverting said capsule,

(b) heating said cooled sealing fluid at said constriction for renderingit fluent to enable release of said valve member from said constriction,and

(c) retaining said valve member following its removal from saidconstriction.

3. A valve sealing method for selectively hermetically sealing anaperture defined by a constriction located intermediate neck and tankportions of a capsule to provide interconnection of said capsule and alight valve tube while maintaining hermetic isolation therebetween andfor removing said hermetic seal to enable the transfer of writing fluidfrom within said tank portion of said capsule to a reservoir within saidlight valve tube, comprising the steps of:

(a) providing a hollow side arm on said neck portion and incommunication therewith at a position remote from said constriction,

(b) positioning a Valve member and viscous sealing fluid within saidside arm, said sealing fluid retaining said valve member within saidside arm,

(c) introducing said writing fluid into said tank portion,

(d) connecting said capsule at said neck portion thereof to anevacuating means for degassing said capsule and said writing fluid,

(e) heating said side arm for rendering said sealing fluid fluent,

(-f) tilting said capsule to extricate said valve memher from said sidearm,

(g) transferring said valve member to said constriction in pluggingrelationship therewith,

(h) heating said sealing fluid and causing it to flow into sealingrelation with said valve member and said constriction, I

(i) cooling said sealing fluid for completing the hermetic valve seal,

(3') inverting said capsule for positioning said neck portion thereofbelow said tank portion and connecting said capsule in hermeticallysealed fashion with said reservoir,

(k) evacuating and degassing said light valve tube,

(1) heating said sealing fluid for rendering it fluent to enable releaseof said valve member from said constriction,

(in) retaining said valve member, "following the removalthereof fromsaid constriction, while transferring said writing fluid to saidreservoir.

4. A valve sealing method as recited in claim 3 further including thesteps of:

(a) providing a feed tube of malleable material extending through saidlight valve tube to provide communication between the reservoircontained therein and said capsule,

(b) mechanically deforming said feed tube following the transfer to saidwriting fluid to said reservoir to provide an hermetic seal thereof,and,

(c) removing said capsule from said light valve tube by severing saidfeed tube at the mechanically deformed portion thereof.

No references cited.

TRAVIS S. McGEHEE, Primary Examiner.

3. A VALVE SEALING METHOD FOR SELECTIVELY HERMETICALLY SEALING AN APERTURE DEFINED BY A CONSTRICTION LOCATED INTERMEDIATE NECK AND TANK PORTIONS OF A CAPSULE TO PROVIDE INTERCONNECTION OF SAID CAPSULE AND A LIGHT VALVE TUBE WHILE MAINTAINING HERMETIC ISOLATION THEREBETWEEN AND FOR REMOVING SAID HERMETIC SEAL TO ENABLE THE TRANSFER OF WRITING FLUID FROM WITHIN SAID TANK PORTION OF SAID CAPSULE TO A RESERVOIR WITHIN SAID LIGHT VALVE TUBE, COMPRISING THE STEPS OF: (A) PROVIDING A HOLLOW SIDE ARM ON SAID NECK PORTION AND IN COMMUNICATION THEREWITH AT A POSITION REMOTE FROM SAID CONSTRICTION, (B) POSITIONING A VALVE MEMBER AND VISCOUS SEALING FLUID WITHIN SAID SIDE ARM, SAID SEALING FLUID RETAINING SAID VALVE MEMBER WITHIN SAID SAID ARM, (C) INTRODUCING SAID WRITING FLUID INTO SAID TANK PORTION, (D) CONNECTING SAID CAPSULE AT SAID NECK PORTION THEREOF TO AN EVACUATING MEANS FOR DEGASSING SAID CAPSULE AND SAID WRITING FLUID, (E) HEATING SAID SIDE ARM FOR RENDERING SAID SEALING FLUID FLUENT, (F) TILTING SAID CAPSULE TO EXTRICATE SAID VALVE MEMBER FROM SAID SIDE ARM, (G) TRANSFERRING SAID VALVE MEMBER TO SAID CONSTRICTION IN PLUGGING RELATIONSHIP THEREWITH, (H) HEATING SAID SEALING FLUID AND CAUSING IT TO FLOW INTO SEALING RELATION WITH SAID VALVE MEMBER AND SAID CONSTRICTION, (I) COOLING SAID SEALING FLUID FOR COMPLETING THE HERMETIC VALVE SEAL, (J) INVERTING SAID CAPSULE FOR POSITIONING SAID NECK PORTION THEREOF BELOW SAID TANK PORTION AND CONNECTING SAID CAPSULE IN HERMETICALLY SEALED FASHION WITH SAID RESERVOIR, (K) EVACUATING AND DEGASSING SAID LIGHT VALVE TUBE, (L) HEATING SAID SEALING FLUID FOR RENDERING IT FLUENT TO ENABLE RELEASE OF SAID VALVE MEMBER FROM SAID CONSTRICTION, (M) RETAINING SAID VALVE MEMBER, FOLLOWING THE REMOVAL THEREOF FROM SAID CONSTRICTION, WHILE TRANSFERRING SAID WRITING FLUID TO SAID RESERVOIR. 